Delta robot is one of the most known parallel systems which possesses high stiffness and accuracy. In order to build a system that endows the robot to perform the desired tasks, an accurate and validate the dynamic model is required. In recent years, researchers have been focused on the construction of serial structured robots. However, few researchers tried to evolve the delta robots in such a system. In this work, the multibody system dynamics (MBS) approach is used to study the kinematics and dynamics of delta robots. A systematic approach is developed based on load assumption due to end-effector movements. The multibody model is constructed using Matlab Symbolic Toolbox. Moreover, D3S-800 is utilized in this study to validate the multibody model. The comparison of experimental data and numerical solution shows a very good agreement and consequently, the multibody model obtained is suitable for parameter identification, control and design optimization of a delta robot system.